The exterior doors of most residences and business today are secured with a keyed lock dead bolt. Such door locks have been available for over a century and have served well. Most of the parts for such door locks were made of brass. However starting the latter years of the twentieth century, steel started to be used for many of the lock components, especially for components of the dead bolt locking assembly (also referred to as the “locking mechanism” herein). Most door keyed cylinder lock assemblies (also referred to as “lock mechanisms” herein) have a cylinder guard (also known as a cylinder ring). The cylinder guard receives a cylindrical lock cylinder (also known as a cylinder) or it receives a cylindrical body which in turn receives a knob-set (lock) cylinder (also known as a key-in-knob cylinder of cylinder or cylinder lock). The cylinder guard, the cylindrical lock cylinder, the cylindrical body, and/or the knob-set cylinder are made of brass. Brass offers many advantages. Brass to some extent is self-lubricating, it is relatively resistant to corrosion, it is easy to cast or mold, it is easy to machine, and it is an attractive metal rich in warm golden tones. Unfortunately, even in view of these attractive features, it has one major drawback. It is relatively expensive compared to some other metals, such as iron, steel, aluminum and zinc. Unfortunately these metals have disadvantages, such as corrosion properties, lack of strength (excluding steel), not as decorative as brass, not self-lubricating, difficult or challenging to mold or cast (excluding zinc and cast iron), not easy to machine (excluding steel), and the like.
Keyed cylinder locks are relatively secure as long as the cylinder cannot be breached. The cylindrical lock cylinders are protected by the mass of the cylindrical lock cylinder housing and the cylinder guard and knob-set cylinders are protected by the cylinder body which holds the knob-set cylinder and is received in the cylinder guard. All these components are relatively large.
Keyed lock dead bolts in doors are relatively secure as long as the dead bolt assembly cannot be breached. If the actuator or actuator assembly of a dead bolt assembly can be reached with an ice pick or similar small diameter implement, the bolt can frequently be defeated quickly and without noise. For this reason, keyed cylinder locks frequently have a shield, such as an anti-pry shield, secured to the cylinder lock mechanism. Many of these shields only extend to, or slightly in, the opening in the door for the bore that receives the lock mechanism and the locking mechanism. The shields do not extend to and cover the actuator of a dead bolt assembly because the shield is secured to the cylinder lock mechanism and it cannot be moved or rotated in the event the lock mechanism or/and the locking mechanism is misaligned. The lock assemblies, i.e. the assembly of lock mechanism and locking mechanism, are made to be somewhat universal to fit on doors having thicknesses of from about 1⅜ to about 1¾ inches. If the shield extended much beyond the back of the lock mechanism, the lock assemblies could not be used on thin doors, such as 1¼ inch thick doors.
It is an object of the present invention to provide a cylinder lock that is secure as existing cylinder locks but uses less brass.
It is another object of the present invention to provide a cylinder lock that uses less brass than existing cylinder locks but uses brass where brass is the material of choice.
It is a further object of the present invention to provide a cylinder lock that uses a knob-set cylinder in a cylinder lock without the need to use a cylinder body for the knob-set cylinder.
It is still an object to provide a cylinder lock wherein the cylinder guard receives the knob-set cylinder without the need for a separate cylinder body.
It is a further object of the present invention to provide a cylinder lock that has a shield that extends from the lock mechanism to and including the locking mechanism.
It is still a further object of the present invention to provide a cylinder lock that has a shield that extends from the lock mechanism to and including the locking mechanism, and is rotatable with respect to the lock mechanism.